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  <title>Document</title>
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<body>
  <ul>
    <li>1</li>
    <li>2</li>
    <li>3</li>
  </ul>

  <ol>
    <li>a</li>
    <li>b</li>
    <li>c</li>
  </ol>

  <script>
    var ol = document.querySelector('ol')

    // console.log( ol.childNodes )
    console.log( ol.children )  // 子元素(标签)节点
  </script>
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